Cesarus85--mjolnir-vr/docs/object_matching_logs/libcmt_constpow_obj.md

libs/libcmt/constpow.obj exact-match ledger

This isolated atomic lane starts from campaign commit 9b666b7d. Before any production edit, constpow.obj was confirmed MISSING at config index 654, absent from config/parked.json, and free of topic branches, worktrees, logs, or active peer ownership.

Plain-English behavior

The CRT's decimal conversion code sometimes has to scale a number by a very large or very small power of ten. This object stores two lookup tables for that job. Each entry is a 12-byte extended-precision value: the normal ten-byte x87 representation plus two extra precision bytes. One table holds positive powers from 10^1 through 10^4096; the other holds the corresponding negative powers.

Primary provenance and January inventory

The authentic XDK 3911 archive member is obj\i386\constpow.obj. Its CodeView records identify Microsoft source ..\constpow.c, compiler ID 0x001c2426, and two arrays in ordinary C. The matching Microsoft 1991-2001 CRT source is also preserved in the public XP SP1 source tree at base/crts/fpw32/conv/constpow.c; it documents that the representation was ported from assembly in 1991 and names the same _pow10pos and _pow10neg tables.

The archive member and January target are strict-identical before any source reconstruction:

• one 700-byte initialized writable .data section with eight-byte alignment and flags 0xC0400040;
• external _pow10pos at offset 0x000;
• external _pow10neg at offset 0x160 (four bytes of compiler-inserted alignment follow the first 348-byte table);
• no relocations, code, .rdata, or .bss;
• normalized SHA-256 1be6b9bcfbebc370831ae298fcf28d4fbfe45d9537d311ef7b9ab09ac525e9f0.

Measured source-shape experiments

ID	One changed factor	Strict measurement	Result
E01	Authentic little-endian Microsoft table initializers, expressed as two arrays of a named 12-byte structure	Target/candidate/archive are 700/700/700 bytes, 0/0/0 relocations, identical normalized SHA, external symbols at offsets 0 and 0x160, and identical section flags	Accepted on the first build

No alternative source shape was tried because E01 reproduced every owned runtime byte and ownership property. The four bytes between arrays are normal VC7 global-data alignment, not an explicit padding field or byte-forcing directive.

Strict validation

• XDK 3911 CL.Exe 13.00.9254.1 rebuilt the source with the unchanged generated /O1 /Gy /I"xbox/include" command.
• section_infos_equal is true for January versus candidate and January versus the authentic archive member. The complete 700-byte owner span, both external symbols, section flags, and absence of relocations agree.
• Full halobetacache_build and libcmt_build succeeded.
• progress credited one complete libcmt object and all 700 data bytes. In this isolated baseline, libcmt reached 86/212 objects, 130/476 functions, 8,895/55,015 code bytes, and 2,428/8,637 data bytes.
• semantic_progress and the explicit semantic audit completed with zero unit errors. The audit evaluated 3,567 functions and accepted 3,483.
• Admission audit found no candidate or revocation for this object. Its sole contradicted source/shell/shell_xbox result is unrelated and pre-existing.
• All 179 tooling tests passed; JSON parsing, git diff --check, prohibited- source review, and scope review were clean.
• The clean-commit regression snapshot/check returned ok: true with no failures or warnings after forcibly deleting and rebuilding the candidate object; the complete non-code owner remained unchanged.

House, Berth, readability, and bug audit

The source preserves Microsoft's named 12-byte representation and names both tables by purpose. Every encoded value is annotated with the mathematical power it represents, so the hexadecimal bytes are reviewable data rather than unexplained magic numbers. These are exact extended-precision constants that cannot safely be rewritten as host long double literals without changing their representation or extra precision.

No assembly, volatile, forced inline/noinline directive, undefined behavior, explicit alignment directive, object-byte patch, flag change, comparator exception, or codegen-only cast is used. The source contains no control flow, pointer arithmetic, tag/datum accesses, or speculative structure offsets. No original behavioral bug was found, so no bug-preservation comment is needed.